Suspicious Perl Command Execution

[rule]
description = """
This rule monitors for suspicious Perl command executions by detecting the start of a Perl process with a command line
argument that contains keywords commonly used by attackers to execute malicious code. These command line arguments
include operations to execute code, create subprocesses, and encode or decode data.
"""
id = "13c404cb-7631-4a33-8b59-5545e9a8a598"
license = "Elastic License v2"
name = "Suspicious Perl Command Execution"
os_list = ["linux"]
version = "1.0.16"

query = '''
process where event.type == "start" and event.action == "exec" and
process.executable like ("/bin/perl*", "/usr/bin/perl*", "/usr/local/bin/perl*") and
process.args == "-e" and process.command_line like~ (
  "*system(*", "*exec(*", "*IO.popen(*", "*Open3.popen3(*", "*spawn(*", "*eval(*",
  "*load(*IO::*", "*load(*Marshal*", "*load(*Fiddle*", "*load(*Zlib*", "*load(*Base64*",
  "*zlib.inflate(*", "*zlib.deflate(*", "*zlib.decompress(*", "*zlib.uncompress(*", "*zlib.compress(*",
  "*Marshal.load(*", "*Fiddle.dlopen(*", "*Fiddle::Function.new(*", "*base64*", "*zlib*", 
  "*net/http*", "*socket.new*", "*open-uri*", "*pack(*"
) and not (
  process.working_directory like~ (
    "/builds/*", "/root/.perl-cpm/*/MIME-tools-*", "/root/.cpan*", "/scratch/*", "/emulator/snmpAgent/net-snmp*",
    "/data1/Axway/TSIM/is/instances/*", "/build/linux-x86_64/__build__/__vmbuild__"
  ) or
  process.command_line like (
    "perl -e eval { use MIME::Base64; print 1; }", "/home/*/bin/sendEmail*", "*transfer fish server*",
    """perl -e $|=1; print "### 100 transfer fish server\n"; while(<STDIN>) { last if /^__END__/; $code.=$_; } exit(eval($code))""",
    "*base64.h*", "*zlib.h*", "*/user/*/Programs/agama/py/schwarzlib.py*", "/usr/bin/perl -MExtUtils::Command -e mkpath -- blib/lib/auto/Compress/Raw/Zlib"
  ) or
  process.parent.name in ("make", "filter_stderr") or
  process.parent.executable like (
    "/var/lib/docker/overlay2/*", "/usr/local/lp/apps/sonarpush-helpers/spectre-meltdown-checker.sh",
    "/usr/sbin/debootstrap", "/usr/bin/xterm", "/usr/bin/xargs", "/var/lib/dpkg/info/sudo.postinst", "/usr/bin/gmake",
    "/usr/bin/gxargs", "/home/*/.vscode-server/*/codex", "/home/*/.npm-global/*/codex", "/usr/local/lib/node_modules/*/codex", "/usr/bin/runc", 
    "/home/*/.nvm/versions/node/*/lib/node_modules/@openai/codex/node_modules/@openai/codex-linux-x64/vendor/x86_64-unknown-linux-musl/bin/codex"
  ) or
  process.parent.command_line like~ ("*testfun()*", "sh -c bash -c testfun*", "/usr/bin/perl t/utf8.t", "*/usr/sap/.call/_call.localhost.*") or
  process.parent.args in ("/usr/bin/parallel", "/usr/sbin/debootstrap") or
  (process.working_directory like "/hana/shared/VN3/*" and process.command_line like "perl -e use MIME::Base64; print decode_base64($ARGV[0]*") or
  (process.parent.executable like "/opt/Kaseya/*/tmp/KcsUpdate" and process.command_line like "perl -MMIME::Base64 -n -e*")
)
'''

min_endpoint_version = "7.15.0"
optional_actions = []
[[actions]]
action = "kill_process"
field = "process.entity_id"
state = 0

[[actions]]
action = "kill_process"
field = "process.parent.entity_id"
state = 0

[[threat]]
framework = "MITRE ATT&CK"
[[threat.technique]]
id = "T1059"
name = "Command and Scripting Interpreter"
reference = "https://attack.mitre.org/techniques/T1059/"


[threat.tactic]
id = "TA0002"
name = "Execution"
reference = "https://attack.mitre.org/tactics/TA0002/"

[internal]
min_endpoint_version = "7.15.0"